Realcraft is a custom server implementation of Minecraft written in REALbasic. It was written in 2011-2013 by Jailout2000 after an argument ensued on Innectis resulting in the rebellious "I can code it better" being said to most of the Innectis community.
This project died as soon as it started. Jailout2000 was able to get as far as spawning into a very flat, grassy world that the only actions anyone could take was walk around a finite land and chat in the server's global chat. There was no inventory, animals/NPCs or other entities, or even autogenerating "chunks" should the player walk to the edge of the world.
This README was added years afterward to explain the remnants of this project. If you wish to continue Realcraft, fork this repository and start making some pull requests.
The last documented version of Minecraft that Realcraft could support was Minecraft 1.3.2 (source). It most likely is not compatible with the current versions of Minecraft.
See the LICENSE.txt file.